(Emphasis mine.) As it happens, this touches on a longstanding peeve (and I am perfectly willing to describe it as such) that I have about the use of positive multipliers to describe the lack of something: twice as small, three times colder. In everyday use, of course, this pattern is readily understood as indicating the reciprocal of the opposite quality: something that's thirty times weaker is actually one-thirtieth as strong. It was interesting to hear Mr. Hays catch himself making the mistake, and then correct himself using more formally precise language—something I think a scientist would be more likely to do than a layperson.

So my question is: Is this really a mistake, or is it actually semantically proper/meaningful to use language indicating a positive magnitude to characterize a concept that is defined specifically as a lack of something else? We don't have a problem using ordinary intensifiers and superlatives in such contexts: a thing can be very small or much weaker. It seems intuitive to me that a multiplier should be treated differently from an intensifier, but I can't actually define why that should be the case. What about the reverse: if twice as small is semantically proper, what about half as small (the obvious ambiguity notwithstanding)? Or are these all more properly thought of as physics or mathematics questions, rather than language questions?

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I don't see a problem with 30 times weaker. 30 times *more* weaker doesn't seem right. more and weaker are not really matching up there; more weak would probably sound OK though.
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FrankAug 24 '14 at 16:19

I assume Hays started to say "more weak," changed it to "weaker" on the fly, then thought better of it and went back to correct the whole thing.
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phenryAug 24 '14 at 16:22

I agree with the peeve. If I'm listening to some positive large integer multiplication, I'm in the mindset to take a reference and increase it by the multiplier. I'm not as likely to switch gears in my head to shrink it by the multiplier.
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SrJovenAug 24 '14 at 16:51

What's the difference (the only measure, I suppose, in English is grammatically cos the spelling is OK) between 30 times stronger and 30 times weaker?
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FrankAug 24 '14 at 18:33

If the first earthquake is at point x on the Richter scale, then, if the second earthquake is at y points, and “thirty times stronger”, y will be 31 times x. To say that the former is “thirty times weaker” than the latter does not make sense mathematically. Thirty times what?
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fdbAug 24 '14 at 18:55

Ignoring the Richter scale, as it's logarithmic, and using a linear scale I don't see the problem, stronger is S=nx, weaker is W=n/x. If your starting point is 5, S=nx = S=5(30) = 150, W=n/x = W=5/30 = 1/6. The difference between S & W where x is the same is always x^2. I think that works for longer/shorter, taller/smaller, fatter/thinner and any positive/negative pair.
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FrankAug 24 '14 at 19:58

'Bad English' meaning 'English that is agreed (by authorities I can quote) to be incorrect' or 'English that I really wish wasn't used, but is, and so I just have to accept it when other people use it'?
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Edwin AshworthAug 24 '14 at 21:56

What would the length of the two sticks, A & B, be if A is three times longer than X and B is three times shorter than X. Given that X is 1 metre long?
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FrankAug 24 '14 at 17:03

@jwpat7 I will fix the second example to avoid confusion.
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Gary's StudentAug 24 '14 at 17:28

@Frank I think A would be three meters long and B would about 33.3 centimeters long.
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Gary's StudentAug 24 '14 at 17:34

That's how I would understand it too, three times shorter is X/3 and three times longer is 3X. Likewise four times shorter is X/4 and four times longer is 4X. So thirty times weaker is W/30. Half as short appears to be the direct translation of twice as short, both being X/2.
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FrankAug 24 '14 at 17:51

Except 'one third shorter' is NOT the same as 'three times shorter'. 'one third shorter' is X-X/3 (66.6), 'three times shorter' is just X/3 (33.3).
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FrankAug 24 '14 at 17:56